What sensor???

[LuckyLobo]

My 89 B2 runs good. But, it has a hard time staying started on the first try... sometime the second try. In the winter, it starts better than the summer. There has to be a sensor that controls the mixture, like a choke would on a carb, but don't know what might be the right culprit. It take a few seconds for the higher idle to kick in. Not a big deal, but sure would like to have it start right up on the first try.

 

[ab_slack]

There are a couple sensors directly related to temperature. The engine coolant temperature (ECT) and air charge temperature (ACT). But there could be something else at play too.

The engine coolant temperature sensor is the main one used to determine if the engine is hot or cold. Determines if it goes into closed loop verses staying in open loop. This is not the same sensor as used for the temperature gauge. The temperature gauge uses a single wire sensor. This is a two wire sensor tucked in just above where the thermostat is housed (where upper rad hose connects to block) and underneath the throttle body or something. It is a royal pain to get at.

Here is a thread I had checking the ECT, RonD provided some good info for checking it.
http://www.therangerstation.com/forums/showthread.php?t=151049


The Air Charge Temperature is one of the sensors used to determine how much fuel. Colder air is denser. The air charge temperature sensor is up on passenger side of the throttle body part way down. Fairly easy to get at. These can get all gummed up with gunk.

 

[NEALD]

My ACT sensor had dirt, gunk and lots of raw fuel on it due to the faulty FPR feeding raw fuel in through the intake tract.